Activation of secondary cells for carrier aggregation and dual connectivity

Abstract

Embodiments include methods and/or procedures for a user equipment (UE) to activate a secondary cell (SCell) for operating with the UE's primary serving cell (PSC). Embodiments include determining a receiver activity rate for the UE. Embodiments also include receiving, from the PSC, an activation request identifying the SCell. Embodiments also include activating the SCell based on the receiver activity rate. Other embodiments include complementary methods and/or procedures performed by a network node arranged to communicate with one or more UEs via a PSC and at least one selectively activated SCell. Other embodiments include UEs and network nodes configured to perform operations corresponding to various ones of the methods and/or procedures, as well as computer-readable media embodying such operations.

What is claimed is: 
     
       1. A method performed by a user equipment (UE) arranged to communicate with a network node in a wireless network via a primary serving cell (PCell) and a selectively activated secondary cell (SCell), the method comprising:
 determining a receiver activity rate for the UE based on a periodic SCell measurement cycle configured for the UE by the network node; 
 receiving, from the network node via the PCell, an activation request identifying the SCell; 
 in response to the activation request, selecting one of a plurality of activation procedures for the SCell based on the receiver activity rate, wherein selecting one of a plurality of activation procedures for the SCell based on the receiver activity rate comprises:
 determining a duration, T, since the UE's last measurement of a signal transmitted by the SCell; 
 determining whether T is greater than a first threshold, T0, that is a function of the receiver activity rate; 
 when T is greater than T0, selecting a first activation procedure; and 
 otherwise, selecting a second activation procedure; and 
 
 activating the SCell according to the selected activation procedure. 
 
     
     
       2. The method of  claim 1 , wherein T0 is an integer multiple of the receiver activity rate. 
     
     
       3. The method of  claim 1 , wherein the first activation procedure comprises:
 measuring power and detecting measurement saturation in each of one or more signal blocks transmitted by the SCell, each signal block being received using one of a plurality of gain settings for a first amplifier; 
 based on the power measurements and saturation detection, selecting one of the gain settings; 
 determining a first receiver gain state corresponding to the SCell, comprising:
 measuring power in a further signal block transmitted by the SCell, the further signal block being received using the selected gain setting for the first amplifier; 
 based on the power measured in the further signal block, determining a gain setting for a second amplifier; and 
 storing the selected gain setting for the first amplifier and the determined gain setting for the second amplifier as the first receiver gain state. 
 
 
     
     
       4. The method of  claim 3 , wherein the first activation procedure further comprises performing the second activation procedure using the stored first receiver gain state. 
     
     
       5. The method of  claim 1 , wherein selecting the second activation procedure comprises:
 determining whether the receiver activity rate is less than a second threshold, T1; 
 when the receiver activity rate is less than T1, selecting a fast second activation procedure having a duration Ta1; and 
 otherwise, selecting a normal second activation procedure having a duration Ta2, wherein Ta2 is greater than Ta1. 
 
     
     
       6. The method of  claim 5 , wherein the normal second activation procedure comprises:
 using the stored first receiver gain state, performing one or more first measurements on a first signal block transmitted by the SCell; and 
 based on the first measurements, performing the following operations:
 updating the stored first receiver gain state to a second receiver gain state; and 
 storing first synchronization information. 
 
 
     
     
       7. The method of  claim 6 , wherein:
 performing one or more first measurements on a first signal block transmitted by the SCell comprises:
 performing at least one first measurement at each of one or more timing offsets covering a range of SCell timing uncertainty; and 
 selecting a particular one of the timing offsets that corresponds to the maximum first measurement for the respective timing offsets; 
 
 the stored first synchronization information is based on the selected timing offset; and 
 updating the first receiver gain state to the second receiver gain state is based on the maximum first measurement corresponding to the selected timing offset. 
 
     
     
       8. The method of  claim 6 , wherein the second normal activation procedure further comprises performing the second fast activation procedure using the second receiver gain state and the first synchronization information. 
     
     
       9. The method of  claim 6 , wherein the second fast activation procedure comprises:
 using the second receiver gain state and the first synchronization information, performing one or more second measurements on a second signal block transmitted by the SCell; and 
 determining channel state information (CSI) for the SCell based on the one or more second measurements. 
 
     
     
       10. The method of  claim 9 , wherein the second fast activation procedure further comprises updating at least one of the stored second receiver gain state and the stored first synchronization information based on the one or more second measurements. 
     
     
       11. The method of  claim 1 , wherein the receiver activity rate is also determined based on one or more of the following parameters:
 discontinuous reception (DRX) cycle periodicity; 
 demodulation reference signal (DRS) occasion periodicity; and 
 SS/PBCH block measurement timing configuration (SMTC) periodicity. 
 
     
     
       12. The method of  claim 1 , further comprising, based on the receiver activity rate, performing one or more measurements on signals transmitted by the SCell. 
     
     
       13. A non-transitory, computer-readable medium storing program instructions that, when executed by at least one processor of a user equipment (UE) arranged to communicate with a network node in a wireless network via a primary serving cell (PCell) and a selectively activated secondary cell (SCell), configure the UE to perform operations corresponding to the method of  claim 1 . 
     
     
       14. A user equipment (UE) arranged to communicate with a network node in a wireless network via a primary serving cell (PCell) and a selectively activated secondary cell (SCell), the UE comprising:
 a radio transceiver; 
 at least one processor; and 
 at least one memory storing program instructions that, when executed by the at least one processor, configure the UE to:
 determine a receiver activity rate for the UE based on a periodic SCell measurement cycle configured for the UE by the network node; 
 receive, via the PCell, an activation request identifying the SCell; 
 in response to the activation request from the PCell, select one of a plurality of activation procedures for the SCell based on the receiver activity rate,
 wherein execution of the instructions configures the UE to select one of a plurality of activation procedures for the SCell based on the receiver activity rate based on: 
 determining a duration, T, since the UE's last measurement of a signal transmitted by the SCell; 
 determining whether T is greater than a first threshold, T0, that is a function of the receiver activity rate; 
 when T is greater than T0, selecting a first activation procedure; and 
 otherwise, selecting a second activation procedure; and 
 
 activate the SCell according to the selected activation procedure. 
 
 
     
     
       15. The UE of  claim 14 , wherein execution of the instructions configures the UE to activate the SCell according to the selected first activation procedure based on:
 measuring power and detecting measurement saturation in each of one or more signal blocks transmitted by the SCell, each signal block being received using one of a plurality of gain settings for a first amplifier; 
 based on the power measurements and saturation detection, selecting one of the gain settings; 
 determining a first receiver gain state corresponding to the SCell, comprising:
 measuring power in a further signal block transmitted by the SCell, the further signal block being received using the selected gain setting for the first amplifier; 
 based on the power measured in the further signal block, determining a gain setting for a second amplifier; and 
 storing the selected gain setting for the first amplifier and the determined gain setting for the second amplifier as the first receiver gain state. 
 
 
     
     
       16. The UE of  claim 15 , wherein execution of the instructions configures the UE to activate the SCell according to the selected first activation procedure further based on performing the second activation procedure using the stored first receiver gain state. 
     
     
       17. The UE of  claim 14 , wherein selecting the second activation procedure further comprises:
 determining whether the receiver activity rate is less than a second threshold, T1; 
 when the receiver activity rate is less than T1, selecting a fast second activation procedure having a duration Ta1; and 
 otherwise, selecting a normal second activation procedure having a duration Ta2, wherein Ta2 is greater than Ta1. 
 
     
     
       18. The UE of  claim 17 , wherein execution of the instructions configures the UE to activate the SCell according to the selected normal second activation procedure based on:
 using the stored first receiver gain state, performing one or more first measurements on a first signal block transmitted by the SCell; and 
 based on the first measurements, performing the following operations:
 updating the stored first receiver gain state to a second receiver gain state; and 
 storing first synchronization information. 
 
 
     
     
       19. The UE of  claim 18 , wherein:
 execution of the instructions configures the UE to perform the one or more first measurements on the first signal block transmitted by the SCell based on:
 performing at least one first measurement at each of one or more timing offsets covering a range of SCell timing uncertainty; and 
 selecting a particular one of the timing offsets that corresponds to the maximum first measurement for the respective timing offsets; 
 
 the stored first synchronization information is based on the selected timing offset; and 
 execution of the instructions configures the UE to update the first receiver gain state to the second receiver gain state based on the maximum first measurement corresponding to the selected timing offset. 
 
     
     
       20. The UE of  claim 18 , wherein execution of the instructions configures the UE to activate the SCell according to the selected normal second activation procedure further based on performing the second fast activation procedure using the second receiver gain state and the first synchronization information. 
     
     
       21. The UE of  claim 18 , wherein execution of the instructions configures the UE to activate the SCell according to the selected fast second activation procedure based on:
 using the second receiver gain state and the first synchronization information, performing one or more second measurements on a second signal block transmitted by the SCell; and 
 determining channel state information (CSI) for the SCell based on the one or more second measurements. 
 
     
     
       22. The UE of  claim 21 , wherein execution of the instructions configures the UE to activate the SCell according to the selected fast second activation procedure further based on updating at least one of the stored second receiver gain state and the stored first synchronization information based on the one or more second measurements.